Lead-in connection for electron discharge tubes



Dec. 30, 1947. l... G. LAWRENCE LEAD-IN' CONNECTION FOR. ELECTRON DISCHARGE TUBES Filed Aug. 22, 1944 Patented Dec. 30, 1947 LEAD-IN CONNECTION FOR ELECTRON DISCHARGE TUBES Leslie G. Lawrence, Newton Highlands, Mass., as-

signor to Raytheon Manufacturing Company, Newton, Mass., a corporation of Delaware Application August 22, 1944, Serial No. 550,614

1 Claim.

rllhis invention relates to electron discharge tubes and more particularly to those of the acorn type.

An object of the present invention is to provide a novel welded connection of the connectorwires to the lead-in wires, whereby the welding and correct mounting of the parts is facilitated and simplified.

Another object of the invention is to insure uniformity of the connector-wire assemblies.

These objects and such other objects and aims of the present invention, as may hereinafter appear, will be readily understood from the following description taken in connection with the accompanying drawing of embodiments of the invention herein presented for illustrative purposes.

In the drawing:

Fig. 1 is a vertical section of an electron discharge tube incorporating one illustrative embodiment of the present invention;

Fig. 2 is a perspective view of the lower portion of an electrode assembly of an electron discharge tube of the acorn type and connections embodying the present invention;

Fig. 3 is a detailed drawing in perspective of the connection, in accordance with the present invention, of the connector-wire with the lead-in wire on the one hand and an element of the electrode assembly on the other hand;

Fig. 4 is a detailed drawing showing an end View of a lead-wire and connector-wire welded thereto in accordance with the present invention;

Fig, 5 is a detailed drawing of a top plan View of the lead-in wire pattern, showing the normal positions of the lead-in wires relatively-to each other and tothe anode or plate of the tube; and

Fig. 6 shows a modification 'of the connectorwire connections according to the present invention.

Heretofore dimculty has been experienced in welding the connector-Wires to the lead-in wires in a uniform manner. Thus, the weld has not always been made at the same spot on the leadin wire, so that the lead-in wires of a tube have not been properly positioned in the latter relatively to each other or to the plate, thus giving rise to objectionable capacity effects or short-circuits in the tube. The connector-wire was also rather easily deformed in handling or welding, so that when a connector-wire, after being welded to a lead-in wire, was inserted in the appropriate spacing perforation in a spacing member, the lead-in Wire could not be correctly clamped upon the spacing member, thus causing the latter to be tipped or displaced to the extent of injuriously affecting not only its own position, but also the positions of other elements in the tube. Even an expert operator could not consistently avoid occurrence of these objectionable results, which have been the cause of many rejects. The present invention overcomes the above difficulties and greatly simplies the welding operation so that it no longer requires an expert operator.

In the drawing, the invention is shown incorporated in an electron discharge tube of the acorn type. Said tube comprises an envelope 2 of glass, or other suitable material, containing an electrode assembly including a cathode 3, preferably of the indirectly heated type (see Fig. 2), an anode or plate 4, and three grids 5, 6 and 'I enclosed within said plate 4..' 'Only the upright supporting posts of said three grids are shown in order not to complicate the drawing. Said posts are mounted in suitable spacing members, four such spacing members 9, I0, II and I2 of mica or other suitable insulating material being herein provided. The two spacing members I0 and I I are relatively close together, while spacing members 9 and I2 are located at the top and bottom, respectively, of the electrode assembly.

A shield I3 encloses the upper part of the electrode assembly and a shield I4 encloses the'lower part thereof between said two mica spacing members II and I2. The plate 4 is connected by a conductor I5 to a lead-in wire I6 sealed through the top of the tube. A lead-in Wire Il, sealed through the bottom of the tube, is connected to the lower end of grid 1. The remaining lead-in wires I8, I9, 28, 2| and 22 are sealed through the side Wall of the tube, three on one side and two on the other side. Lead-in wires I8 and 20 are connected, respectively, to heating wires 23 and 24 of the cathode 3, and lead-in wires I9, 2I and 22 are connected, respectively, to the cathode 3, grid 5 and grid 6. (See Figs. 2 and 5.) 'I'hese connections are made in a novel manner and by means of a novel connector-wire inaccordance with the present invention. Referring to the case of lead-in wire I9, it will be noted (see Fig. 2) that the connector-wire 25 is welded to the end surface of the lead-in wire I9, diametrically of said surface, that is to say, in a plane containing the longitudinal axis of said lead-in wire. The other end of said connector-wire will preferably be inserted through spacing perforations in one or more of said spacing members, through the spacing members I0, II and I2, for example, and its lower end bent up against the under surface of said spacing member I2 to clamp said lead-in wire firmly down upon the upper surface of said spacing member I0. In the case of lead-in wires I8, 20, 2| and 22, the connector-wires 26, 21, 2B and 29 are bent over at one end, for example, in the form of a U, and one shank, shank 30, for example, of the U-shaped end, is welded to the end surface of the lead-in wire, also diametrically of said i'surface, both shanks k30 and'3l being in the same plane, yinthe present instancein a plane containing the longitudinal axis of the leadin wire. Both shanks 30 and 3l, of said connector-Wires, will be inserted through corresponding spacing perforations of one or more of said spaing members, the shank 30 through the spacing member I0, for example (see Fig. 2), andbent up against its lower surface to clamp the yleadin wire firmly down upon said spacing member, while the shank 3l is connected tothe proper electrode element, as previously stated.

In the modification shown in Fig. 6 the weld of the connector-wire 32 to the end surface of the the other end of-said conductor wire being welded to a gridvpost 35 or other Vdesired element of the Aelectrode structure below said spacing member.

From the above description it will be seenthat by welding Vthe connector-,wire to the-end sur- .face of the lead-in vwire -and diametrically of said surface, in accordance with the present invention, the welded connection isautomatically l'located in the corrected position, and when the connector-wires of the various lead-inlwires have --beeninserted through theappropriate perforations of the predetermined pattern inthe spac- ,ing member, `the various lead-in wires willbe vcorrectly positioned within the tube, both rela- ,tively to one another and relatively to the plate. mAll danger'of short-circuiting between adjacent lead-in Wiresfor between a lead-in wire or leadin-wires and the plate is excluded. Furthermore, deformation of connector-wires in handlingfor welding 'can'be easily avoided, so that difiiculty in clamping the lead-in wires into close --contact with the spacing member is avoided. Lead-in Wires are usually provided with a coating to cushion stresses due to unequal expansion of said wires and the glass of the envelope through fwhich they are welded, and heretofore it has been necessary to remove said coating before fweldi-ngaconnector-wire to a lead-in Wire. welding' the connector-fwire to the end lsurface of the lead-in wire, which surface is not coated, this precaution becomes unnecessary. It will be noted that in the embodiment of the present invention using a connector-wire with a U-shaped end only one shank of the U-shaped end is welded to the end surface of the lead-in wire, so that should the spacing of the two shanks not correspondrexactly to thatof the two perforations through which they are to be inserted in a spacing member, the shank that has not been welded to the end surface of the lead-in wire can easily zbe adjusted at the right distance from the welded shank to enable both shanks to be inserted :through said perforations without diiculty and vwithout .riskof forcing said Shanks or fracturving said spacing member, in order correctly to vposition said lead-in wire upon said spacing member.

4Iam aware that the present invention can be embodied in other specific forms without departing from the spirit or essential attributes there of, and I therefore desire the present description to be considered in all respects as illustrative and not restrictive, reference being had to the appended claim rather than to the aforesaid description toindicate the scope of the invention.

What is claimed is:

In an electron discharge tube, the -combination of a spaced member having two spacing perforations, an electrode element, a lead-in wire, and a connector-wire for electrically connecting said .lead-in wire to said electrode element, said connector-wire having a U-shaped end, one shank of said U-shaped end being Welded to an end surface'of said lead-in wire diametrically of said surface, the two Shanks of said U-shaped end of said connector-\vire being inserted through said spaced perforations, the free end of one shank being bent into contact with said spacing member to clamp said lead-in wire to the latter, the other shank being joined to said electrode element.

LESLIE G. LAWRENCE.

REFERENCES rCITED The following referencesfare of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2,017,549 -Salzbergl fOct. l5, 1935 1,965,338 Gibson etal July 3, 1934 2,086,578 Samuel July 13, 1937 2,030,187 Salzberg 1--- Feb. 11, 1936 2,267,450 Ekstrandet al -...Dec. 23, 1941 

